Diagnosis and Management of Tinea Infections JOHN W. ELY, MD, MSPH; SANDRA ROSENFELD, MD; and MARY SEABURY STONE, MD University of Iowa Carver College of Medicine, Iowa City, Iowa Tinea infections are caused by dermatophytes and are classified by the involved site. The most common infections in prepubertal children are tinea corporis and tinea capitis, whereas adolescents and adults are more likely to develop tinea cruris, tinea pedis, and tinea unguium (onychomycosis). The clinical diagnosis can be unreliable because tinea infections have many mimics, which can manifest identical lesions. For example, tinea corporis can be confused with eczema, tinea capitis can be confused with alopecia areata, and onychomycosis can be confused with dystrophic toe- nails from repeated low-level trauma. Physicians should confirm suspected onychomycosis and tinea capitis with a potassium hydroxide preparation or culture. Tinea corporis, tinea cruris, and tinea pedis generally respond to inex- pensive topical agents such as terbinafine cream or butenafine cream, but oral antifungal agents may be indicated for extensive disease, failed topical treatment, immunocompromised patients, or severe moccasin-type tinea pedis. Oral terbinafine isfirst-line therapy for tinea capitis and onychomycosis because of its tolerability, high cure rate, and low cost. However, kerion should be treated with griseofulvin unless Trichophyton has been documented as the pathogen. Failure to treat kerion promptly can lead to scarring and permanent hair loss. (Am Fam Physician. 2014;90(10):702- 710. Copyright © 2014 American Academy of Family Physicians.) More online he term tinea means fungal infec- (Figure 1). Lesions may be single or multi- at http://www. tion, whereas dermatophyte refers ple and the size generally ranges from 1 to aafp.org/afp. to the fungal organisms that cause 5 cm, but larger lesions and confluence of CME This clinical content tinea. Tinea is usually followed by lesions can also occur. Tinea corporis may conforms to AAFP criteria Ta Latin term that designates the involved be mistaken for many other skin disorders, for continuing medical education (CME). See site, such as tinea corporis and tinea pedis especially eczema, psoriasis, and sebor- CME Quiz Questions on (Table 1). Tinea versicolor (now called pity- rheic dermatitis (Table 2).2,3 A potassium page 696. riasis versicolor) is not caused by derma- hydroxide (KOH) preparation is often help- Author disclosure: No rel- tophytes but rather by yeasts of the genus ful when the diagnosis is uncertain based evant financial affiliations. Malassezia. Tinea unguium is more com- on history and visual inspection. Worsen- ▲ Patient information: monly known as onychomycosis. Dermato- ing after empiric treatment with a topical A handout on this topic is phytes are usually limited to involvement of steroid should raise the suspicion of a der- available at http://family hair, nails, and stratum corneum, which are matophyte infection. Conversely, if a non- doctor.org/familydoctor/ inhospitable to other infectious agents. Der- fungal lesion is treated with an antifungal en/diseases-conditions/ tinea-infections/treat matophytes include three genera: Tricho- cream, the lesion will likely not improve or ment.html. phyton, Microsporum, and Epidermophyton. will worsen. Cultures are usually not neces- The most common infections in prepu- sary to diagnose tinea corporis.2 Skin biopsy bertal children are tinea corporis and tinea with periodic acid–Schiff (PAS) stain may capitis, whereas adolescents and adults are rarely be indicated for atypical or persistent more likely to develop tinea cruris, tinea lesions. pedis, and tinea unguium (onychomycosis). Tinea cruris (jock itch) most commonly Tinea infections can be difficult to diagnose affects adolescent and young adult males, and treat. In one survey, tinea was the skin and involves the portion of the upper thigh condition most likely to be misdiagnosed by opposite the scrotum (Figure 2). The scro- primary care physicians.1 tum itself is usually spared in tinea cruris, but involved in candidiasis. A Wood lamp Tinea Corporis, Tinea Cruris, examination may be helpful to distinguish and Tinea Pedis tinea from erythrasma because the causative Tinea corporis (ringworm) typically pres- organism of erythrasma (Corynebacterium ents as a red, annular, scaly, pruritic patch minutissimum) exhibits a coral red fluores- with central clearing and an active border cence. However, results of the Wood lamp 702Downloaded American from the Family American Physician Family Physician website at www.aafp.org/afp.www.aafp.org/afp Copyright © 2014 American AcademyVolume of Family90, Number Physicians. 10 For◆ November the private, 15,noncom 2014- mercial use of one individual user of the website. All other rights reserved. Contact [email protected] for copyright questions and/or permission requests. Tinea Infections SORT: KEY RECOMMENDATIONS FOR PRACTICE Evidence Clinical recommendation rating References examination can be falsely negative if the Tinea corporis, tinea cruris, and tinea pedis can C 2 often be diagnosed based on appearance, but a patient has bathed recently. potassium hydroxide preparation or culture should Tinea pedis (athlete’s foot) typically be performed when the appearance is atypical. involves the skin between the toes, but can Acceptable treatments for tinea capitis, with shorter A 14-16 spread to the sole, sides, and dorsum of the treatment courses than griseofulvin, include involved foot (Figure 3). The acute form pres- terbinafine (Lamisil) and fluconazole (Diflucan). ents with erythema and maceration between The diagnosis of onychomycosis should generally C 27 be confirmed with a test such as potassium the toes, sometimes accompanied by painful hydroxide preparation, culture, or periodic acid– vesicles. The more common chronic form Schiff stain before initiating treatment. is characterized by scaling, peeling, and erythema between the toes; however, it can A = consistent, good-quality patient-oriented evidence; B = inconsistent or limited- quality patient-oriented evidence; C = consensus, disease-oriented evidence, usual spread to other areas of the foot. Involvement practice, expert opinion, or case series. For information about the SORT evidence of the plantar and lateral aspects of the foot rating system, go to http://www.aafp.org/afpsort. with erythema and hyperkeratosis is referred to as the “moccasin pattern” of tinea pedis.4 Tinea corporis, tinea cruris, and tinea pedis can often be diagnosed based on appearance, but a KOH prepara- Table 1. Fungal Infections of the Skin tion or culture should be performed when the appear- ance is atypical.2 Dermatophytes Tinea corporis (ringworm), includes tinea gladiatorum and MANAGEMENT tinea faciei Tinea corporis, tinea cruris, and tinea pedis are gener- Tinea capitis (ringworm of the scalp) ally responsive to topical creams such as terbinafine Tinea cruris (jock itch) (Lamisil) and butenafine (Lotrimin), but oral antifungal Tinea pedis (athlete’s foot) agents may be indicated for extensive disease, failed topi- Tinea unguium (onychomycosis) Tinea manuum (commonly presents with “one-hand, two- cal treatment, immunocompromised patients, or severe feet” involvement) moccasin-type tinea pedis. Patients with chronic or Tinea barbae (beard infection in male adolescents and adults) recurrent tinea pedis may benefit from wide shoes, dry- Tinea incognito (altered appearance of dermatophyte infection ing between the toes after bathing, and placing lamb’s caused by topical steroids) wool between the toes.5 Patients with tinea gladiato- Candida (yeast) and mold, which may cause onychomycosis or rum, a generalized form of tinea corporis seen in wres- coexist in a dystrophic nail tlers, should be treated with topical therapy for 72 hours Pityriasis versicolor (formerly tinea versicolor) caused by before return to wrestling.6 Malassezia species Uncommon fungal skin infections that involve other organs Several pitfalls of managing tinea infections are listed (e.g., blastomycosis, sporotrichosis) in Table 3.2,7,8 Tinea Capitis In the United States, tinea capitis most commonly affects children of African heritage between three and nine years of age.4 There are three types of tinea capi- tis: gray patch, black dot, and favus. Black dot, caused by Trichophyton tonsurans, is most common in the United States (Figure 4). Early disease can be limited to itching and scaling, but the more classic presentation involves one or more scaly patches of alopecia with hairs broken at the skin line (black dots) and crusting. Tinea capitis may progress to kerion, which is characterized by boggy tender plaques and pustules. The child with tinea capi- tis will generally have cervical and suboccipital lymph- adenopathy, and the physician may need to broaden the differential diagnosis if lymphadenopathy is absent.7 Figure 1. Tinea corporis. November 15, 2014 ◆ Volume 90, Number 10 www.aafp.org/afp American Family Physician 703 Table 2. Differential Diagnosis of Tinea Infections Differential diagnosis Distinguishing features Tinea corporis (annular lesions with well-defined, scaly, often reddish margins; commonly pruritic) Annular psoriasis Gray or silver scale; nail pitting; 70% of affected children have family history of psoriasis2 Atopic dermatitis Personal or family history of atopy; less likely to have active border with central clearing; lesions may be lichenified Erythema multiforme Target lesions; acute onset; no scale; may have oral lesions Fixed